1. Unit 3 Lesson 5 Plant Hormones and Their Effects
1/17/2019
Unit 3, Lesson 5, Plant Hormones and Their Effects

2. Functions of Plant Hormones
Plant hormones are chemicals that are produced in one part of the plant and transported to another part, where it causes a physiological change.
1/17/2019
Unit 3, Lesson 5, Plant Hormones and Their Effects

3. Types of Plant Hormones
There are four common types of plant hormones:
Auxins
Gibberellins
Cytokinins
Ethylene
1/17/2019
Unit 3, Lesson 5, Plant Hormones and Their Effects

4. Unit 3, Lesson 5, Plant Hormones and Their Effects
Description of Auxins
With Auxins
Auxins promote cell elongation.
It weakens the connections between the cellulose fibers in the cell wall, which allow them to stretch and grow longer.
Auxins promote stem growth
Without Auxins
1/17/2019
Unit 3, Lesson 5, Plant Hormones and Their Effects

5. Description of Gibberellins
Gibberellins also promote cell elongation.
Dwarf plants are often “dwarfed” because they cannot produce gibberellins or can’t process it.
Fruit farmers use it to enhance fruit formation.
1/17/2019
Unit 3, Lesson 5, Plant Hormones and Their Effects

6. Description of Cytokinins
Cytokinins stimulate cell division (cytokinesis).
They produce more proteins by promoting mitosis.
Cytokinins are produced in the roots.
1/17/2019
Unit 3, Lesson 5, Plant Hormones and Their Effects

7. Description of Ethylene Gas
Ethylene is a simple, gaseous compound composed of carbon and hydrogen that speeds the ripening of fruit.
Ethylene causes the cell walls to become soft and causes the fruit to become sweet.
1/17/2019
Unit 3, Lesson 5, Plant Hormones and Their Effects